Shoulder blade pain,lung cancer?

Im 18 years old, and just a few days ago I started feeling some pain in my shoulder/shoulder blade area stretching forward under the chest. Its scaring me a little as I started smoking about a year ago, which I am planning on quitting as soon as possible. but I don't have any breathing or coughing problems, I have been feeling tired and at times sweat excessively and just feel kind of feverish. I did some research and I'm starting to think its ether phenomia, gall bladder infection or even lung cancer. kinda scary but hoping for the best, ill be seeing a doctor as soon as possible.